For decades phosphorus in the form of zinc diorgano dithiophosphates (ZDDPs) has been used as extreme pressure (EP) and antiwear additives in engine oils. A problem with the use of phosphorus, however, is that it contaminates emissions control systems catalysts and thereby reduces their effectiveness. In response to this problem, phosphorus concentration has been reduced for some SAE passenger car engine oil classifications. With the introduction of ILSAC GF-1, phosphorus levels were limited to no more than 1200 parts per million (ppm) and with GF-3 to 1000 ppm. Even at these levels of phosphorus, however, catalyst contamination is still an issue. The problem therefore is to provide adequate engine lubrication and at the same time reduce catalyst contamination. The present invention provides a solution to this problem.